Polyurethane elastomers which are useful for this purpose are characterized by a post-cure durometer hardness (as determined by ASTM Dl706-61 durometer Type A Test) of the order of about 35 to about 80, by high tear strength, by their ability to adhere to substrates such as glass, cement, aluminum, steel, iron and like metals, and by their resistance to corrosion on exposure to the atmosphere, to